Clutch and brake mechanism for presses



Jan. 3, 1950 T.'L. MAY 2,493,495

CLUTCH AND BRAKE MECHANISM FOR PRESSES Filed Dec. 30, 1944 5Sheets-Sheet 1 INVEN TOR.

zjmdo BY Jan. 3, 1950 T. 1. MAY I 2,493,495

. CLUTCH AND BRAKE MECHANISM FOR PRESSES Filed Dec. 30. 1944 5Sheets-Sheet 2 Q 2? 5 ,l G) 37 3'3 50 o I I I I 36 I I l I INVENTOR.

- BY v 74 ATTO/PN Y5 Jan. 3, 1950 T. L. MAY v 2,493,495

CLUTCH AND BRAKE MECHANISM FOB PREQSES Filed Dec. 30, 1944 r 5Sheets-Sheet 3 a &

Jan. 3, 1950 1'. 1,. MAY 2,493,495

CLUTCH AND BRAKE MECHANISM FOR PRESSES- Filed Dec. 30, 1944 5Sheets-Sheet 4 2; TO/ /VEYS Jan. 3, 1950 MAY 2,493,495

CLUTCH AND BRAKE: MEC'HANISM FOR PRESSES Filed D60. 30, 1944 5Sheets-Sheet 5 IN V EN TOR.

Patented Jan. 3, 1950 CLUTCH AND BRAKE MECHANISM FOR PnEssEs ThomasLestler May, New YorlcxN. Y.,. assignor, by mesneassignments, toReliance Hydraulic Press, Inc., New York, N, Y.,. a corporation of NewYork Application December 30, 194%, Serial'No. 570,621 2 Claims. (01.192 -17.).

This invention relates to flywheel type punch presses.

An object of this invention is a flywheel punch presswhich is reliablein operation, can be operatedv at high speed, is silent in operation,has a long, efficient life and is of simple construction..

In a flywheel punch press embodying this invention, hydraulic means areprovided for clutching and declutching the flywheel and crank shaft andadditional hydraulic means are provided for applying and releasing brakemeans for the crank shaft. Cams rotatable with the crank shaft actuatefour-way fluid valves to control the flow of hydraulic fluid to and fromboth hydraulic means. By reason of this structure, the noisy clickingincidental to mechanical ciut'c'h and brake-operating means is avoided,thereby rendering silent the operation of the press. Means also areprovided for preventing operation of the hydraulic means to clutch theflywheel and crank shaft except when the operators both hands are in aposition of safety. Also; the press frame is mounted on a base forlimited. tilting movement whereby the angularity of the frame may bevaried.

Other objects, novel features and advantages of this invention willbecome apparent from the followingspecification and accompanyingdrawings, wherein:

Fig. 1 is a front elevation of a press constructed in'accordance withthe invention;

Fig. 2 is a side elevation;

Fig. 3 is a section on the line 3-3 of Fig. 2;

Fig. 4 is a fragmentary end view of Fig. 3;

Fig. 5 is a section on the line 5-5 of Fig. 3;

Fig. 6 is a section substantially on the line 6-6 of Fig. 3;

Fig. 7 is a side elevation of Fig. 6, and

Fig. 8 is a hydraulic diagram.

A base ID has a frame ll pivotally connected thereto by means of shafts12. A hollow member I3 is pivotally supported at one end by the pin [-4mounted in the base l and. in itsv free end the member [.3 receives arotatable member 15. having a plurality of. radial recesses IS. Themembers 13 and I are provided with co-operating shoulders to limitmovement of the member 15 toward the pivot pin I4 and the member l5is-provided with a peripheral groove I1 into which projects the innerend of a screw 18 mounted in the member l3 to prevent withdrawal of themember l5 from the member 13. The member l5 has a. threaded. bore inwhich is arranged a lag screw "3, the upper; end of which hasatransverse here through which passes a pin l9, the ends of which arearranged in ears 20 formed on. the frame II. The shaft I2 is locatednear. the front of the base and the lag screw 1:8, in combination withits associated parts, provides means for tilting the frame H at anydesired angle upon rotation of the member |5 through the medium of a barinserted in the recesses 16. The frame ll carries a pin 2! projectingthrough an arcuate slot 22 in the base I'll concentric with the pivotpin l2 and serves to limit the extent of tilting of the frame II as wellas to: indicate the extent of tilting by reason of indicia provided insuitable relationship to the slot 22 for that purpose.

A crank shaft 23 is journalled in the frame II and a pitman rod 24 isattached in the usual manner to the crank pin 25 of the crank shaft 23.The-lower end of the pitman rod is attached in -the usual manner to ahead 26 slidably supported by vertical guides 21 for movement toward andaway from the bed 28 in the usual manner. The frame I I supports a motor29 and an. oil pump 30 which is driven by the motor through themedium ofa belt 3|.

A flywheel 3-2 is journallecl on one end of the crank shaft 23 and isdriven by the motor 29 through :the medium of a belt 33. A thrustbearing. 34. is interposed between one face of the flywheel 32 and. ashoulder 35 on the crank shaft 23. A circular clutch element 36 is heldagainst the outer face of the flywheel 32 by bolts 3"!- and is providedwith an inner tapering surface 38. A hub 39 is supported by the crankshaft 23 and is keyed thereto by a spline 40 so that the hub and shaftrotate in unison and the hub is movable axially of the shaft. A circularclutch element 4| is attached to the hub 39 by bolts 42 and has an outerconical face 43 complementary tothe face 38 of the clutch element 36. Astrip 44 of standard clutch facing material fixed to the clutch element4! and is arranged between the surfaces 43 and 38.

The extreme end of the crank shaft 23 has a threaded portion 45 ofreduced diameter and a circular piston 46 has an interiorly threadedbore co-operating with the threaded portion 45 to attach the piston tothe end of the shaft. A block 41 has a cylindrical bore 41a of twodifferent diameters with the smaller diameter por- .tion. receiving thecrank shaft and the larger diameter :portion receiving the piston 46.The block "is attached to the collar 39v by bolts .48. Ahead. 49 fltstheouter end of the block 41 and has anrextension 50. .A passageway 51leads from the inner end of the cylinder to a radial 54. Ports 58 and 59in the cap communicate with the recesses 56 and 51 respectively.

valve 80 and between said valve and the hydraulic motor 10.

The arrangement is such that with the clutch inoperative and the brakeoperative, the cam followers !4 and 15 contact the low sections 125 and13b of the cams 12 and I3, as indicated in Figs. 4 and 5 near thetrailing ends thereof. With the parts in the position shown in Figs. 4and 5, the

Z valve plungers 19a and 80a are in such position A brake drum 60 isfixed to the remaining end of the crank shaft 23by a key 6|. A splitbrake band 62 is supported by the frame through the medium of a post 63and is provided with a suitable brake lining 63a. The two secthathydraulic fluid is supplied under pressure to the upper end of thehydraulic motor 10 to locate the roller 68 out of engagement with thebrake sections to permit the spring 64 to hold the brake sectionsagainst the drum 60 to oppose rotation of the crank shaft and hydraulicfluid is supplied under pressure to the outer end of the j cylinder 41a.to hold it and the drum 4| with tions of the brake band are urged towardthe V drum 52 by a spring 64 arranged on a rod 65 ex-' tending throughthe free ends of both of the band sections and having nuts'66 and 61 atthe opposite ends thereof with the spring 64 arranged between one bandsection and the nut 61 which is adjustable to vary the tension exertedby the spring 64. A roller 68 is carried by a yoke at the end of thepiston 69 of a hydraulic motor I0. The roller 68 is adapted to beprojected by the hydraulic motor between the ends of the brake sectionsfor the purpose of stretching apart the band sections to release thecrank shaft. Upon withdrawal of the roller 68, the spring 64 urges theband sections into engagement with the brake drum 60 to oppose rotationof the shaft 23.

A sleeve H is keyed to the crank shaft 23 and is provided with a pair ofcams l2 and I3 which have high sections 12a and 13a respectively and lowsections 121) and 13b respectively. Cam followers l4 and 15 forco-operation with the peripheries of the cams l2 and 13 respectively arearranged at the ends of levers 16 and I1 respectively, fulcrum'ed at acommon pivot pin 18. A pair of standard four-way fluid valves 19 and 80are suitably arranged below the free ends of the levers l8 and Hrespectively for actuation thereby. The valves 19 and 80 have actuatingplungers m and 800. respectively, as well as springs 19b and 80brespectively for normally maintaining the plunger in a predeterminedadjustment. The plungers 19a and 80a are located respectively in thepaths of the ends of the levers I6 and J1 opposite the cam followers 14and 15. A rod 8| slidably carries a cross-bar 82 engaging the uppersurfaces of the levers l6 and TI on the opposite side of the pivot pin18 from the cam followers. A spring 83 is interposed between the crossbar and a nut 84 on the end of the rod. The rod 8| is mounted in guides85 and at its lower end is connected to the upper end of link 86, thelower end of which is connected to one arm of a bell crank lever 81, theother end of which is connected by'a cable 88 passing over suitableguide rollers 89 and 90 to a foot pedal 9|. The arrangement is such thatupon depression of the pedal 9|, the rod 8| is caused to movedownwardly.

the clutch facing 46 out of engagement with the member 36 so that theflywheel 32 rotates freely on the shaft 23. The pedal 9| is in itsuppermost position to which position it is biased by the springs 19b andb. Upon depression'of the pedal 9|, the levers 16 and T! are tilted-tolift the cam followers 14 and 15 and to depress both valve plungers 19aand 80a whereupon the supply of hydraulic fluid to the motor 10 isreversed to force the roller 68 between the ends of the brake sectionsto release the crank shaft 23 for rotation. Also, the supply ofhydraulic fluid to the cylinder 41 is reversed to apply pressure urgingthe cylinder 41 in the direction to engage the clutch facing 44 with thesurface 38 to clutch the flywheel to the crank shaft to cause rotationof the latter. The cams 12 and I3 rotate clockwise from the positionshown in Fig.4 to locate the high sections 12a and 13a under the camfollowers to hold the levers l6 and 11 tilted after the release of thepedal 9|. After predetermined extent of rotation of the crank shaft, thecam followers ride off the high sections 12a and 13a into contact withthe low sections 121) and 13b thereby permitting return of thefourwayvalves l9 and '80 to their original positions under the influenceof their springs and corresponding return of the levers l6 and 11 tooriginal position. The extent of the high section 13a isgreater than theextent of the high section 12a so that the clutch is released before thebrake is actuated. The hydraulic motor 10 is thereupon actuated towithdraw the roller 68 from between the ends of the brake band sectionsand also the clutch hydraulic motor is actuated to disengage the clutchfacing 44 from the surface 38 thereby stopping the crank shaft after onecomplete revolution.

Declutching of the flywheel from the crank shaft is facilitated bysprings-91 seated in sockets in the hub 39 and bearing against a collar98 attached to the crank shaft 23 and engaging the flywheel 32. Asuitable packing 99 provides a fluid-tight seal between the crank shaft23' and the block 41. The ehd of the cap 55 is formed as a detachablecover I00 and a plate |0| attached to the end of the shaft 23 by boltsI02 holds the cap in position on the shaft against a shoulder |03. Ateach end'of the cap 55 there is provided a circular chamber I04connecting with a longitudinal chamber I05 arranged below the extension50. The cover I00 closes one chamber I04 while a sealing member I06closes the other. Any hydraulic fluid which escapes along the surface ofthe extension 50 from the grooves 52 and 54 is conducted by the chambersI04 to the chamber I05 from which it is returned through 5 the pipe N11to the reservoir of the hydraulic system.

Each of the cams 12 and 13 is so constructed as to permit change of theeffective length of the high sections 72a and 13a respectively and lowsections 125 and 731) respectively. This construction will be describedonly in connection with cam 12 but it is to be understood that the cam13 is of the same construction. The cam 72 is provided with a lowsection 122) of definite length and the cam supports an arcuate member98 by studs I09 passing through arcuate slots I I in the cam 12 coaxialtherewith. The member I08 is provided with high and low sections I081)and [08a corresponding to the high and low sections 72a and 122'). Byrotatable adjustment of the member I08 the effective lengths of the highand low sections of the cam may be varied within limits thereby varyingthe timing of the valve 19.

The press is equipped with mechanism to prevent operation of it exceptwhen the operators hands are both in positions of safety. A bleed I Hleads from the pipe 94 through which the hydraulic fluid is supplied tothe clutch-operating hydraulic motor for the purpose of clutching theshaft 23 to the flywheel 32. The bleed H l is controlled by a valve I I2operated by a solenoid I IS, the arrangement being such that with thesolenoid deenergized, the valve is opened allowing hydraulic fluid topass through the bleed from the pipe 94 to a reservoir (not shown). Theenergizing circuit for the solenoid includes a pair of palm switches H4and H arranged in front of the press bed 28 (Fig. 1). These switches areself-opening and are closed by downward pressure of the operators handsand both switches must be closed in order to energize the solenoid H3.Should the pedal 9| be tripped with either switch H4 and H5 open, thepressure of the hydraulic fluid supplied to the clutch-operating motorwill be insufficient to energize it because of the fact that the bleed lI I is open and hydraulic fluid is by-passed therethrough to thereservoir. In order to clutch the flywheel 32 to the shaft 23, bothswitches H4 and H5 must be closed and the pedal 9| depressed.

It is of course understood that various modifications may be made in thedevice above described without in any way departing from the spirit ofthe invention as defined in the appended claims.

I claim:

1. A punch press comprising a rotatable crank shaft, a flywheeljournalled on said shaft, means for clutching and declutching saidflywheel and crank shaft, a hydraulic motor for actuating said means, abrake mechanism for said crank shaft, means including a hydraulic motorfor actuating said brake mechanism, and means including cam membersrotatable with said crank shaft for regulating flow of hydraulic fluidto and from said hydraulic motors, each cam member having a high sectionand a low section, a pivoted lever associated with each cam member andprovided with a cam follower, means biasing said levers and camfollowers toward said cam members, and means including a pedal forrotating said levers contrary to said biasing means.

2. A punch press according to claim 1 characterized by said cam membersbeing so related to each other that both motors are simultaneouslyoperated and are successively operated first to declutch said flywheeland then to apply said brake mechanism.

THOMAS LESTLER. MAY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 312,146 Merritt Feb. 10, 1885615,441 Emmerich et a1 Dec. 6, 1898 769,955 Osswald Sept. 13, 1904975,589 Watkins Nov. 15, 1910 1,544,766 Leschhorn July '7, 19251,547,355 Bayer et al July 28, 1925 1,869,085 Williamson July 26, 19321,894,434 Williamson Jan. 17, 1933 2,068,062 Metten Jan. 19, 19372,085,040 Post June 29, 1937 2,120,798 C'riley June 14, 1938 2,204,710Strout June 18, 1940

